Negative glow lamp



Jam, W E949. m. E; ELMENDQR NEGATIVE GLOW LAMP Filed Oct. 4, 1946 Inven'l'or- Durvgea E. Elmenol'or'fi His ATTorrwey.

Patented Jan. 18, 1949 UNITED STATES PATENT OFFICE NEGATIVE GLOW LAMP Duryea. E. Elmendorf, Cleveland, Ohio, assignor to General Electric Company, a corporation of New York This invention relates to gaseous electric discharge devices of the type employing ionizable mediums such as gases or vapors and more particularly to an electrode structure for use in a glow discharge lamp.

An object of my invention is toprovide a new and improved electrode structure for electric discharge devices.

Another object of my invention is to provide a new and improved inexpensive electrode structure which may be manufactured and assembled on automatic equipment.

A further object of my invention is to provide a rugged ele trode structure affording a balanced, symmetrical. appearance.

Further features and advantages of my invention willappear from the following description and species thereof.

For a better understanding of my invention reference may be had to the following description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims. Fig. 1 is a side elevation of a glow discharge device incorporating my invention. Fig. 2 is a side elevation, partlyin section, of an electrode structure for a glow discharge lamp incorporating my invention. Fig. 3 is a side elevation of a glow discharge device illustrating a modification of Fig. 1. Fig. 4 and Fig. 5 illustrate modifications of the electrode structure shown in Fig. 2.

With reference to Fig. 1, I provide a new and improved electric discharge device or glow lamp i. The lamp 9 comprises a vitreous envelope 2 having sealed into the end thereof a stem 3 (which stem and electrode structure are shown in enlarged view in Fig. 2/ and which may comprise a stem press or squeeze 4 employed to furnish a mechanical support for lead-in wires 5 and 6 and to fuse and secure these wires through stem 3. Lead-in wires 5 and B, serve as supports for electrode structure including a pair of spaced electrodes 7 and 8 defining a gap 9 constructed according to my invention, and which permit electrical connection to the electrode structure from a source of ,current. In order to reduce the over-all axial or longitudinal dimension of the electrode structure, I provide electrodes 7 and 8, preferably constructed of pro-formed sheet material, such as nickel, formed to surround the upper part of stem 3 and more particularly the stem squeeze thereby reducing the axial length of the electrode structure. Electrodes i' and B comprise a pair of spaced axially aligned bands or electrodes of annular configuration, of conductive material embodying grooves or indentations l0 and II. Lead-in wires 5 and 6 are formed with transversely or laterally positioned or extending arcuate inner end portions l2 and I3 concentric with bands 1 and 8 and having a snap or spring-biased interlocking engagement with the bands within arcuate indentations l0 and II therein. A preferable means of securing bands I and 8 to the lead-in wires 5 and B may be obtained by forming lead-in wires 5 and 5 with diametrically opposed arcuate inner end portions. Electrodes i and 8, for example, may be coated with an alkaline earth metal preferably barium or strontium oxides or mixtures thereof, and the inner surface of these electrodes are preferably coated with an insulative coating such as aluminum oxide suspended in amyl acetate and nitrocellulose or aluminum paint, or the like, in order to confine the glow to the outer electrode surfaces. It is obvious, however, that these electrodes may be formed out of bi-metal, such as a composite assembly comprising an outer surface of nickel and an inner surface of aluminum.

An exhaust tube It is provided for exhaustion .and sealing off envelope 2. A suitable atmosphere, such as a gas or vapor, is provided within the sealed envelope 2. This atmosphere, for example, may eonsist of argon containing 5 to 20% of nitrogen at a pressure from 6 to 20 millimeters of mercury. A preferable mixture giving exceptionally good results has been found to be neon containing about 0.8 of a percent of argon at a pressure of about 35 millimeters of mercury. Lead-in wire 6 may consist of a. composite conductive member embodying two spaced wires electrically connected by a resistive element I5. The resistor i 5 by virtue of its location within the stem in place of the base renders possible a reduction in the size and cost of a lamp base required therewith.

Pig. 3 incorporates the same described corresponding parts of Fig. 1 and Fig. 2, except annular electrode 8 is replaced by a cap shaped electrode l6 embodying an indentation M.

Fig. 5 illustrates a modification of the electrode structure shown in Fig. 4 and embodies the corresponding parts except that stem 3 is replaced by a four-wire stem l8. Lead-in wires 5 and 6 are replaced by two pairs of lead-in wires l9 and 20, and 2| and 22, respectively, each pair having diametrically opposed arcuate inner end portions concentric with one of the annular bands and having a snap or spring-biased interlocking en- 3 gagement with the band within annular indentation therein.

In accordance with my invention I provide a new" and improved rugged electrode structure designed for assembly and manufacture on automatic machinery. Accordingly, I provide an electrodejstructure affording a well balanced and symmetrical appearance,

Generally speaking, I effect these desired results by providing an electrode structure embodying constituent parts economically prefabricated and automatically assembled with the minimum of manufacturing steps. In other words, I provide an electrode structure embodying electrodes capable of being firmly secured to the structure by means of snap spring-biased interlocking engagement in place of the usual costly welding operations.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of electrodes comprising spaced axially aligned bands of conductive material, a pair of lead-in Wires fused through said stem and having transversely extending inner end portions secured to said electrodes within indentations therein.

charge device comprising in combination a vitreous stem, a pair of electrodes comprising spaced axially aligned bands of conductive material, a

pair of lead-in wires fused through said stem and having transversely extending inner end portions secured to said electrodes within annular indentations therein.

4. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of electrode comprising spaced axially aligned bands of conductive material, and

a pair of lead-in wires fused through said stem and having laterally extending arcuate inner end portions concentric with said annular bands and having a snap interlocking engagement with said bands within annular indentations therein.

5. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of electrodes comprising spaced axially aligned annular bands of conductive material, and two pairs of lead-in wires fused through said stem and each pair having diametrically opposed arcuate inner end portions concentric with one of said annular bands and having a snap interlocking engagement with one of said bands within an annular indentation therein.

6. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of metallic electrodes of annular configuration, a pair of lead-in wires fused through said stem and having transversely positioned inner end portions secured to said electrodes by extending into indentations therein.

7. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of spaced metallic electrodes of annular configuration, a pair of lead-in wires fused through said stem and including transversely extending inner end portions having a spring biased interlocking engagement with said electrodes within indentations therein.

8. An electrode structure for an electric discharge device comprising in combination a vitreous stem, a pair of spaced metallic axially aligned annular electrodes one of which is cap shaped, a pair of lead-in wires fused through said stem and having transversely positioned inner end portions secured to said electrodes within indentations therein.

DURYE'A E. ELMENDORF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,984,469 Ewest Dec. 18, 1934 2,421,571 Leyshon June 3, 1947 

